270 gsm- Tired of warm, half-frozen mush around your mouth when wearing a balaclava on cold winter days? The Comet Balaclava can help you out, big time. Duckworth's proprietary Comet fabric is natural-technical mash-up, combining a pure, 100% Montana-grown Merino Wool outer layer and a polyester inner layer. Why the combo? Polyester is hydrophobic, meaning it will wick sweat, humid breath, and moisture right off your skin and into the hydrophilic wool layer; wool chemically begins to get even warmer when introduced to water and water vapor, thus explaining why the Comet Balaclava will have your face and head feeling dry and toasty even in the nastiest, coldest, most-humid conditions. By the way, Comet is soft to the touch, perfect for resting on your chin or over your mouth and nose (or a bald head, as is the case with some of the Duckworth staff!).